So close, and yet so far. Prisoners at Alcatraz, the federal maximum-security penitentiary known as the Rock, had a tantalizing view of San Francisco, but the mile-and-a-half span between the two landmasses was virtually unbridgeable. Escapees drowned, froze or were eaten by sharks-if they weren't shot or captured first. Spanish explorers named the island Isla de los alcatraces, or island of gannets, in 1775 because the cormorants here reminded them of similar fowl in Spain. The first inmates arrived in the 1850s, when it was a military fortress. The military transferred jurisdiction to the US Department of Justice in 1933 and for the next 30 years, the penitentiary was home to the most desperate and irredeemable criminals in the US, including Al Scarface Capone, Machine Gun Kelly, and Robert Birdman Stroud. The conditions were brutal, with one guard to every three prisoners, a strict no-talking policy, and dark holes of solitary confinement for rule breakers. Thirty-six men tried to escape; it's still not clear if the most famous attempt, made by three men in 1962, was successful. Their bodies were never found.After the last inmates were transferred in 1963, the island fell vacant until 1969, when a group of Native Americans occupied it, citing an 1868 treaty granting them the right to claim uninhabited federal land. The campaign was unsuccessful, and in 1972, Alcatraz was designated part of the Golden Gate National Recreation Area. Tours of the ruins have been fascinating visitors ever since.